1. Field of the Invention
This invention relates generally to low pressure gas regulators, and particularly to a low pressure gas regulator for purging a vessel of gas, and charging it with another gas.
2. Prior Art
There has been a long-felt need for a simple low pressure gas regulator by means of which vessels may be evacuated and recharged with a purging gas. Numerous elaborate systems have been known, but none have been suitable for laboratory use, nor have there been any which have been simple in character. For example, reference is made to Smith U.S. Pat. No. 2,522,969 of Sept. 19, 1950; Jonas U.S. Pat. No. 2,711,842 of June 26, 1955; Gutter U.S. Pat. No. 3,164,170 of Jan. 5, 1965. None of these devices are primarily suited for laboratory use which would allow an operator to remove an undesirable atmosphere from an apparatus or vessel and substitute a desirable atmosphere. There appears to be no known simple, foolproof apparatus which requires but little attention from the operator, and needs but the operation of a single valve to accomplish its purpose. Moreover, existing systems may utilize large quantities of purging gas before the objective is accomplished. It is often desirable to effect economies under such circumstances.